Download QNET Rotary Pendulum Laboratory Manual

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Acknowledgements
Quanser, Inc. would like to thank the following contributors:
Dr. Hakan Gurocak, Washington State University Vancouver, USA, for his help to include embedded outcomes assessment, and
Dr. K. J. Åström, Lund University, Lund, Sweden for his immense contributions to the curriculum content.
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Contents
1
Introduction
4
2
Simple Modeling
2.1
Background
2.2
Simple Modeling Virtual Instrument
2.3
Damping [15 min]
2.4
Friction [15 min]
2.5
Moment of Inertia [30 min]
2.6
Results
6
6
8
8
9
9
11
3
Balance Control Design
3.1
Background
3.2
Balance Control Design VI
3.3
Model Analysis [20 min]
3.4
Control Design and Simulation [45 min]
12
12
12
14
15
4
Balance Control
Implementation
4.1
Background
4.2
Balance Control VI
4.3
Default Balance Control [30 min]
4.4
Implement Designed Balance Control [20 min]
4.5
Balance Control with Friction
Compensation [30 min]
18
18
18
19
20
21
5
Swing-Up Control
5.1
Background
5.2
Swing-Up Control VI
5.3
Energy Control [30 min]
5.4
Hybrid Swing-Up Control [20 min]
24
24
26
26
27
6
System Requirements
6.1
Overview of Files
6.2
Simple Modeling Laboratory VI
6.3
Control Design VI
6.4
Swing-Up Control VI
29
29
29
30
30
7
Lab Report
7.1
Template for Content (Simple Modeling)
7.2
Template for Content (Balance Control Design)
7.3
Template for Content (Balance Control Implementation)
7.4
Template for Content (Swing-Up Control)
7.5
Tips for Report Format
36
36
37
38
39
40
8
Scoring Sheets
8.1
Simple Modeling: Pre-Lab Questions
8.2
Simple Modeling Lab Report
8.3
Balance Control Design: Lab Report
8.4
Balance Control Implementation: Lab Report
8.5
Swing-Up Control: Lab Report
41
41
42
43
44
45
A
QNET Instructor's Guide
A.1
Pre-lab Questions and Lab Experiments
A.2
Assessment for ABET Accreditation
A.3
Rubrics
46
46
47
53
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INTRODUCTION
Regulation and servo problems are very common, but feedback can be used in many other useful ways. The name
task-based control is used as a common classification of a wide variety of problems. For instance, stabilization of
an unstable system can be considered a task-based problem. However, it is a borderline example since it can also
be viewed as a regulation problem. The Segway transporter is a typical example where stabilization is a key task.
In that case stabilization is also merged with the steering functions. Other examples are damping of a swinging load
on a crane, stabilization of a rocket during take-off, and the human posturing systems. There are many examples
of task-based control in aerospace such as automatic landing and orbit transfer of satellites. Robotics is a rich field
for task-based control with challenges such as collision avoidance, motion planning, and vision based control. Taskbased control is typically more complicated than regulation and servoing but they may contain servo and regulation
functions as sub-tasks. We have chosen the rotary pendulum system to illustrate task-based control
The QNET rotary inverted pendulum trainer is shown in Figure 1.1. The motor is mounted vertically in a metal
chamber. An L-shaped arm is connected to the motor shaft and pivots between ±180 degrees. A pendulum is
suspended on a horizontal axis at the end of the arm. The pendulum angle is measured by an encoder. The control
variable is the input voltage to the pulse-width modulated amplifier that drives the motor. The output variables are
the angle of the pendulum and the angle of the motor.
Figure 1.1: QNET rotary inverted pendulum trainer (ROTPENT)
There are three experiments: simple modeling, inverted pendulum balance control, and swing-up control. The
experiments can be performed independently.
Topics Covered
• Modeling the pendulum
• Balance control (via state-feedback)
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• Control optimization (LQR)
• Friction compensation
• Energy control
• Hybrid control
Prerequisites
In order to successfully carry out this laboratory, the user should be familiar with the following:
• Transfer function fundamentals, e.g. obtaining a transfer function from a differential equation.
• Using LabVIEWr to run VIs.
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SIMPLE MODELING
2.1 Background
This experiment illustrates some control tasks for gantry cranes. The gantry is a moving platform or trolley that
transports the crane about the factory floor or harbor. The load hangs from the crane using wires and is moved by
the gantry crane. Typically the problem is to move the load quickly and move it to the correct position. The fast
motion necessary for production makes it more difficult to move the load to the correct location given the swinging
motions of the crane. This problem can be mimicked using the rotary pendulum system by viewing the tip of the
L-shaped arm as the moving trolley and the pendulum tip as the load being carried.
In this experiment we will begin by modeling the system and determine strategies to dampen the oscillations of the
system.
Figure 2.1: Free-body diagrams of pendulum assembly
Figure 2.1 shows the free-body diagram of the pendulum assembly that is composed of two rigid bodies: the pendulum link with mass Mp1 and length Lp1 , and the pendulum weight with mass Mp2 and a length Lp2 . The center of
mass of the the pendulum link and the pendulum weight are calculated separately using the general expression
∫
p x dx
xcm = ∫
p dx
where x is the linear distance from the pivot axis and p is the density of the body. The circle in the top-left corner of
Figure 2.1 represents the axis of rotation or the pivot axis that goes into the page.
The pendulum system is then expressed as one rigid body with a single center of mass, as shown in Figure 2.2.
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Figure 2.2: Free-body diagram of composite pendulum
The center of mass of a composite object that contains n bodies can be calculated using
∑n
mx
∑n i cm,i
xcm = i=1
i=1 mi
where xcm,i is the known center of mass of body i and mi is the mass of body i.
From the free-body diagram in Figure 2.2, the resulting nonlinear equation of motion of the pendulum is
Jp α̈(t) = Mp g lp sin α(t) + Mp u lp cos α(t)
(2.1)
where Jp is the moment of inertia of the pendulum at the pivot axis z0 , Mp is the total mass of the pendulum assembly,
u is the linear acceleration of the pivot axis, and lp is the center of mass position as depicted in Figure 2.2. Thus as
the pivot accelerates towards the left the inertia of the pendulum causes it to swing upwards while the gravitation
force Mp g and the applied force Mp u (the left-hand terms in Equation 2.1) pull the pendulum downwards.
The moment of inertia of the pendulum can be found experimentally. Assuming the pendulum is unactuated, linearizing Equation 2.1 and solving for the differential equation gives the expression
Jp =
Mp g lp
4f 2 π 2
(2.2)
where f is the measured frequency of the pendulum as the arm remains rigid. The frequency is calculated using
f=
ncyc
∆t
(2.3)
where ncyc is the number of cycles and ∆t is the duration of these cycles. Alternatively, Jp can be calculated using
the moment of inertia expression
∫
J=
r2 dm
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v 1.0
where r is the perpendicular distance between the element mass, dm, and the axis of rotation.
In addition to finding the moment of inertia, this laboratory investigates the stiction that is present in the system. The
rotor of the DC motor that moves the ROTPEN system requires a certain amount of current to begin moving. In
addition, the mass from the pendulum system requires even more current to actually begin moving the system. The
friction is particularly severe for velocities around zero because friction changes sign with the direction of rotation.
See Wikipedia for more information on: center of mass, inertia, pendulum, and friction.
2.2 Simple Modeling Virtual Instrument
The virtual instrument for studying the physics of the pendulum when in the gantry configuration is shown in Figure
2.3.
Figure 2.3: LabVIEW VI for modeling QNET rotary pendulum.
2.3 Damping [15 min]
1. Ensure the QNET ROTPENT Simple Modeling VI is open and configured as described in Section 2.2. Make
sure the correct Device is chosen.
2. Run the QNET ROTPENT Simple Modeling.vi shown in Figure 2.3.
3. Hold the arm of the rotary pendulum system stationary and manually perturb the pendulum.
4. While still holding the arm, examine the response of Pendulum Angle (deg) in the Angle (deg) scope. This is
the response from the pendulum system.
5. Repeat 3 above but release the arm after several swings.
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6. B-5, B-7 Examine the Pendulum Angle (deg) response when the arm is not fixed. This is the response from
the rotary pendulum system. Given the response from the pendulum and rotary pendulum system, which
converges faster towards angle zero? Why does one system dampen faster than the other?
Answer 2.1
Outcome
B-5
B-7
Solution
If the procedure was followed correctly, they should be able to draw
some conclusions based on examined responses.
The rotary pendulum system converges to angle zero more rapidly. The
rotary pendulum system is naturally more damped due to the coupling
effect between the rotary arm and pendulum link.
7. Stop the VI by clicking on the Stop button.
2.4 Friction [15 min]
1. Run the QNET ROTPENT Simple Modeling.vi.
2. In the Signal Generator section set
• Amplitude = 0 V
• Frequency = 0.25 Hz
• Offset = 0.0 V
3. Change the Offset in steps of 0.10 V until the pendulum begins moving. Record the voltage at which the
pendulum moved.
4. Repeat Step 3 above for steps of -0.10 V.
5. B-5, B-7 Enter the positive, Vf p , and negative voltage, Vf n , values needed to get the pendulum moving. Why
does the motor need a certain amount of voltage to get the motor shaft moving?
Answer 2.2
Outcome
B-5
B-7
Solution
If the procedure was followed correctly, they should be able to draw
some conclusion based on examined responses.
The positive and negative Coulomb friction voltages recorded are Vf p =
2.1 V and Vf n = −2.9 V. These results will vary between QNET ROTPEN
systems. To overcome the friction in the motor, a certain amount of
current is required to make the rotor move. The amount of voltage in
either direction varies between 1.0 V and 3.0 V.
6. Stop the VI by clicking on the Stop button.
2.5 Moment of Inertia [30 min]
2.5.1 Pre-Lab Questions
1. A-1, A-2 Find the moment of inertia acting about the pendulum pivot using the free-body diagram. Make
sure you evaluate numerically using the parameters defined in the QNET ROTPEN User Manual ([2]).
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Answer 2.3
Outcome
A-1
A-2
Solution
Use Equation 2.4 with the pendulum free-body diagram given in Figure
2.1 to find its moment of inertia.
Using Equation 2.4 on the FBD in Figure 2.1
∫
Jp
∫
Lp1
0
=
Lp1 +Lp2
r2 dr + p2
= p1
r2 dr
Lp1
1
1
Mp1 L2p1 + Mp2 L2p1 + Mp2 Lp1 Lp2 + Mp2 L2p2 .
3
3
When evaluated with the pendulum parameters given in the QNET Rotary Pendulum User Manual ([2]),
Jp = 6.98 × 10−4 kg · m2
2.5.2 In-Lab Exercises
1. Run the QNET ROTPENT Simple Modeling.vi.
2. In the Signal Generator section set
• Amplitude = 1.0 V
• Frequency = 0.25 Hz
• Offset = 0.0 V
3. Click on the Disturbance toggle switch to perturb the pendulum and measure the amount of time it takes for
the pendulum to swing back-and-forth in a few cycles (e.g., 4 cycles).
4. B-5, K-1 Find the frequency and moment of inertia of the pendulum using the observed results. See Section
2.1 to see how to calculate the inertia experimentally.
Answer 2.4
Outcome
B-5
K-1
Solution
If they were able to follow the procedure properly, then they should be
able to measure the number of cycles.
After performing the experiment, the pendulum goes through 6 cycles in
2.5 s. Using Equation 2.3, the frequency is
f=
6
= 2.4 Hz
2.5
Substituting this and the pendulum parameters defined in [2] in Equation
2.2,
0.0270 × 9.81 × 0.153
Jp,exp =
= 1.77 × 10−4 kg · m2
4 × 2.42 × π 2
5. B-9 Compare the moment of inertia calculated analytically in Exercise 1 and the moment of inertia found
experimentally. Is there a large discrepancy between them?
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Answer 2.5
Outcome
B-9
Solution
The moment of inertia found analytically is 6.98 × 10−4 kg · m2 while
the experimentally determined inertia is 1.77 × 10−4 kg · m2 . This discrepancy may be due to an inaccuracy when measuring the pendulum
frequency or the fact that this frequency is the damped frequency (not
the undamped natural frequency that the equation to compute the inertia
uses).
6. Stop the VI by clicking on the Stop button.
2.6 Results
Fill out Table 1 with your answers from above.
Description
Section 2.4: Friction
Positive Coulomb Friction Voltage
Negative Coulomb Friction Voltage
Section 2.5: Moment of Inertia
Calculated inertia
Experimentally found inertia
Symbol
Value
Unit
Vf p
Vf n
2.1
-2.9
V
V
Jp
Jp,exp
6.98 × 10−4
1.77 × 10−4
kg · m2
kg · m2
Table 1: QNET ROTPENT Modeling results summary
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BALANCE CONTROL DESIGN
3.1 Background
A rich collection of methods for finding parameters of control strategies have been developed. Several of them have
also been packaged in tools that are relatively easy to use. Linear Quadratic Regulator (LQR) theory is a technique
that is suitable for finding the parameters of the balancing controller in Equation 4.1 in Section 4. Given that the
equations of motion of the system can be described in the form
ẋ = Ax + Bu
the LQR algorithm computes a control task, u, to minimize the criterion
∫ ∞
J=
x(t)T Qx(t) + u(t)T Ru(t)dt
0
The matrix Q defines the penalty on the state variable and the matrix R defines the penalty on the control actions.
Thus when Q is made larger, the controller must work harder to minimize the cost function and the resulting control
gain will be larger. In our case the state vector x is defined
[
x= θ
]T
α
θ̇
α̇
Since there is only one control variable, R is a scalar and the control strategy used to minimize cost function J is
given by
u = −K(x − xr ) = −kp,θ (θ − θr ) − kp,α (α − π) − kd,θ θ̇ − kd,α α̇.
The LQR theory has been packaged in the LabVIEWr Control Design and Simulation Module. Thus given a model
of the system in the form of the state-space matrices A and B and the weighting matrices Q and R, the LQR function
in the Control Design Toolkit computes the feedback control gain automatically. In this experiment, the model is
already available. In the laboratory, the effect of changing the Q weighting matrix while R is fixed to 1 on the cost
function J will be explored.
See Wikipedia for more information on optimal control.
3.2 Balance Control Design VI
The QNET ROTPENT Control Design VI has three tabs. Each tab is explained in the following sections.
3.2.1 Symbolic Model Tab
The Symbolic Model tab shown in Figure 3.1 is used to setup the QNET rotary pendulum model.
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Figure 3.1: LabVIEW VI to generate state-space model of QNET rotary pendulum.
3.2.2 Open Loop Analysis Tab
The Open Loop Analysis tab on the VI is used to analyze the open loop stability of the QNET rotary pendulum
system, shown in Figure 3.2.
Figure 3.2: LabVIEW VI used to analyze open loop stability of QNET rotary pendulum system.
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3.2.3 Simulation Tab
On the Simulation tab shown in Figure 3.3, users can generate the balance control gains for the QNET rotary
pendulum system using LQR and simulate the closed-loop system.
Figure 3.3: LabVIEW VI for QNET rotary pendulum balance control design.
3.3 Model Analysis [20 min]
1. Open the QNET ROTPENT Control Design.vi.
2. Run the QNET ROTPENT Control Design.vi. The front panel of the VI shown in Figure 3.1.
3. Select the Symbolic Model tab.
4. The Model Parameters array includes all the rotary pendulum modeling variables that are used in the statespace matrices A, B, C, and D.
5. Select the Open Loop Analysis tab, shown in Figure 3.2.
6. B-5, B-7 This shows the numerical linear state-space model and a pole-zero plot of the open-loop inverted
pendulum system. What do you notice about the location of the open-loop poles? How does that affect the
system?
Recommended: In the Model Parameters section, it is recommended to enter the pendulum moment of inertia,
Jp, be determined experimentally in Section 2.5.
Answer 3.1
Outcome
B-5
B-7
Solution
If the VI was ran correctly, they should be able to draw some conclusions
based on the pole locations.
The inverted rotary pendulum system is unstable because there is one
pole in the right-hand plane.
7. In the Symbolic Model tab, set the pendulum moment of inertia, Jp, to 1.0 × 10−5 kg · m2 .
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8. K-1, B-9 Select the Open Loop Analysis tab. How did the locations of the open-loop poles change with the
new inertia? Enter the pole locations of each system with a different moment of inertia. Are the changes of
having a pendulum with a lower inertia as expected?
Answer 3.2
Outcome
K-1
B-9
Solution
The poles are at {9.0,-9.2,-0.35,0} for Jp = 1.7 × 10−4 kg · m2 and {11,11.3,-0.35,0} for Jp = 1.0 × 10−5 kg · m2 .
The poles in the right-hand plane (RHP) move further into the RHP when
the inertia is decreased. This implies that it's is easier to stabilize or balance an inverted pendulum that has a larger moment of inertia. Which
makes sense from a practical standpoint, e.g., it's easier to balance a
broom stick with one hand then it is a pencil.
9. Reset the pendulum moment of inertia, Jp, back to 1.77 × 10−4 kg · m2 .
10. Stop the VI by clicking on the Stop button.
3.4 Control Design and Simulation [45 min]
1. Open the QNET ROTPENT Control Design.vi.
2. Select the Simulation tab.
3. Run the VI. The VI running is shown Figure 3.3.
4. In the Signal Generator section set:
• Amplitude = 45.0 deg
• Frequency = 0.20 Hz
• Offset = 0.0 deg
5. Set the Q and R LQR weighting matrices to the following:
• Q(1,1) = 10, i.e., set first element of Q matrix to 10
• R=1
Changing the Q matrix generates a new control gain.
6. B-5, K-1 The arm reference (in red) and simulated arm response (in blue) are shown in the Arm (deg) scope.
How did the arm response change? How did the pendulum response change in the Pendulum (deg) scope.
Answer 3.3
Outcome
B-5
K-1
Solution
If the VI was ran correctly, they should be able to make the following
observations.
The arm response becomes faster, i.e., peak time decreases, mainly
due to the increased arm proportional gain. In the pendulum tends to
deflect form its vertical position more as the gain is increased, however.
7. Set the third element in the Q matrix to 0, i.e., Q(3,3) = 0.
8. B-7 Examine and describe the change in the Arm (deg) and Pendulum (deg) scope.
QNET ROTPENT Laboratory Manual - Instructor Manual
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Answer 3.4
Outcome
B-7
Solution
Decreasing this LQR term makes the arm response faster but the pendulum angle tends to overshoot more. The proportional and derivative
gains of the pendulum go down when Q(3,3) decreases.
9. K-3 By varying the diagonal elements of the Q matrix, design a balance controller that adheres to the following
specifications:
• Arm peak time less than 0.75 s: tp ≤ 0.75 s.
• Motor voltage peak less than ± 12.5 V: |Vm | ≤ 12.5 V.
• Pendulum angle less than 10.0 deg: |α| ≤ 10.0 deg.
Record the Q and R matrices along with the control gain used to meet the specifications in your report.
Answer 3.5
Outcome
K-3
Solution
Using the weighting matrices


40 0 0 0
 0 1 0 0

Q=
 0 0 0 0
0 0 0 1
and R = 1, the following gain was generated
[
]
K = −6.32 81.2 −2.76 10.87
(Ans.3.1)
10. K-2, B-9 Attach the responses from the Arm (deg), Pendulum (deg), and Control Input (V) scopes when
using your designed balance controller. Does it satisfy the specifications?
Answer 3.6
Outcome
K-2
B-9
Solution
The simulated closed-loop response of the QNET rotary inverted pendulum is given in Figure 3.4. This is using the LQR gain given in Equation
Ans.3.1.
The response in Figure 3.4 meets the specifications given in Step 9.
11. Stop the VI by clicking on the Stop button.
QNET ROTPENT Laboratory Manual - Instructor Manual
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(a) Rotary Arm
(b) Pendulum Link
(c) Motor Voltage
Figure 3.4: Simulated rotary inverted pendulum response.
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4
BALANCE CONTROL
IMPLEMENTATION
4.1 Background
Balancing is a common control task. In this experiment we will find control strategies that balance the pendulum
in the upright position while maintaining a desired position of the arm. When balancing the system the pendulum
angle, α, is small and balancing can be accomplished simply with a PD controller. If we are also interested in keeping
the arm in a fixed position a feedback from the arm position will also be introduced. The control law can then be
expressed as
u = −kp,θ (θ − θr ) − kp,α (α − π) − kd,θ θ̇ − kd,α α̇
(4.1)
where kp,θ is the arm angle proportional gain, kp,α is the pendulum angle proportional gain, kd,θ is the arm angle
derivative gain, and kd,α is the pendulum angle derivative gain. The desired angle of the arm is denoted by θr and
there is no reference for the pendulum angle because the desired position is zero.
There are many different ways to find the controller parameters. As discussed in Section 3.1, one method is based
on LQR-optimal control. Initially, however, the behaviour of the system will be explored using default parameters.
When balancing the pendulum over a fixed point, the arm tends to oscillate about that reference because of the
friction present in the motor. Due to friction, the motor will not move until the control signal is sufficiently large and
the generated torque is larger than the stiction (see Section 2.1 for more details). This means that the pendulum
has to fall a certain angle before the motor moves and the net result is an oscillating motion.
Friction can be compensated by introducing a Dither signal at the input voltage of the DC motor. The Dither signal
used has the form
Vd = Ad sin fd t + Vd0
where Ad is the voltage amplitude, fd is the sinusoid frequency, and Vd0 is the offset voltage of the signal.
See Wikipedia for more information on PID and friction.
4.2 Balance Control VI
The virtual instrument used to run the balance controller (and the swing-up, shown later) on the QNET rotary pendulum system is shown in Figure 4.1.
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Figure 4.1: LabVIEW VI for QNET rotary pendulum balancing control (and swing-up).
4.3 Default Balance Control [30 min]
1. Open the QNET ROTPENT Swing Up Control.vi and ensure it is configured as described in Section 6. Make
sure the correct Device is chosen.
2. Run the QNET ROTPENT Swing Up Control.vi. The VI should appear similarity as shown in Figure 4.1.
3. In the Signal Generator section set:
• Amplitude = 0.0 deg
• Frequency = 0.10 Hz
• Offset = 0.0 deg
4. In the Balance Control Parameters section set:
• kp theta = -6.5 V/rad
• kp alpha = 80 V/rad
• kd theta = -2.75 V/(rad/s)
• kd alpha = 10.5 V/(rad/s)
5. In the Swing-Up Control Parameters section set:
• mu = 55 m/s2/J
• Er = 20.0 mJ
• max accel = 10 m/s2
• Activate Swing-Up = OFF (de-pressed)
6. Adjust the Angle/Energy (deg/mJ) scope scales to see between -250 and 250 (see Reference [2] for help).
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7. Manually rotate the pendulum in the upright position until the In Range? LED in the Control Indicators section
turns bright green. Ensure the encoder cable does not interfere with the pendulum arm motion.
8. B-5, K-1 Vary Offset and observe the Arm Angle (deg) response in the Angle/Energy (deg/mJ) scope. Do
not set the Offset too high or the encoder cable will interfere with the pendulum arm motion.
Answer 4.1
Outcome
B-5
K-1
Solution
If the VI was ran correctly and the pendulum is being balance, then they
should be able to make some observations below.
The Offset input box in the Signal Generator generates a constant setpoint. The rotary arm is stabilized about the set offset angle.
9. K-1 As the pendulum is being balanced, describe the red Arm Angle (deg) and the blue Pendulum Angle
(deg) responses in the Angle/Energy (deg/mJ) scope.
Answer 4.2
Outcome
K-1
Solution
Both are stabilized but students may notice that the rotary arm tends to
rotate back-and-forth about the set offset angle.
10. In the Signal Generator section set:
• Amplitude = 45.0 deg
• Frequency = 0.10 Hz
• Offset = 0.0 deg
11. B-7 Observe the behaviour of the system when a square wave command is given to the arm angle. Why
does the arm initially move in the wrong direction?
Answer 4.3
Outcome
B-7
Solution
This is necessary to keep the pendulum balanced. If the arm didn't go
back a bit before moving forward then the pendulum would have a tendency to rotates downwards and go unstable. The technical answer is
the system is non-minimum phase.
12. Click on the Stop button to stop running the VI.
4.4 Implement Designed Balance Control [20 min]
1. Go through Section 3.4 and design a balance control according to the given specifications.
Remark: It is recommended to use the experimental determined pendulum moment of inertia that was found
in Section 2.5.
2. Open the QNET ROTPENT Swing Up Control.vi and ensure it is configured as described in Section 6. Make
sure the correct Device is chosen.
3. Run the QNET ROTPENT Swing Up Control.vi. The VI should appear similarity as shown in Figure 4.1.
4. In the Signal Generator section set:
• Amplitude = 45.0 deg
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• Frequency = 0.20 Hz
• Offset = 0.0 deg
5. To implement your balance controller, enter the control gain found in Section 3.4 in kp theta, kp alpha, kd theta,
and kd alpha in the Control Parameters section.
6. Manually rotate the pendulum in the upright position until the In Range? LED in the Control Indicators section
turns bright green. Ensure the encoder cable does not interfere with the pendulum arm motion.
7. B-5, K-2, B-9 Attach the response found Angle/Energy (deg/mJ) and the Voltage (V) scopes. Does your
system meet the specifications given in Section 3.4?
Answer 4.4
Outcome
B-5
K-2
B-9
Solution
If the student was able to get the response given in Figure 4.2, then the
procedure to run the VI was done properly.
The measured closed-loop response of the QNET rotary inverted pendulum is given in Figure 4.2. This is using the LQR gain given in Equation
Ans.3.1.
As shown in Figure 4.2, the arm peak time is around 0.75 seconds, the
input motor voltage is within ± 10.5 V, and the pendulum oscillates ±
5 deg about the vertical position. So the specifications given in Section
3.4 are satisfied.
(a) Rotary Arm, Pendulum Angle, and Energy
(b) Motor Voltage
Figure 4.2: Simulated rotary inverted pendulum response.
8. Click on the Stop button to stop running the VI.
4.5 Balance Control with Friction
Compensation [30 min]
1. Go through steps 1-7 in Section 4.3 to run the default balance control. The pendulum should be balancing.
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2. In the Signal Generator section set:
• Amplitude = 0.0 deg
• Frequency = 0.10 Hz
• Offset = 0.0 deg
3. In the Dither Signal section set:
• Amplitude = 0.00 V
• Frequency = 2.50 Hz
• Offset = 0.00 V
4. B-5, B-8 Observe the behaviour of Arm Angle (deg) in the Angle/Energy (deg/mJ) scope. Intuitively speaking,
can you find some reasons why the arm is oscillating?
Answer 4.5
Outcome
B-5
B-8
Solution
If the procedure was followed correctly and pendulum is balancing, they
should be able to make the following analysis.
Due to static friction found in motor, it typically takes at least ± 2.5 V
to get the rotor moving. As a result, the pendulum has to fall enough
such that the balance controller generates over ± 2.5 V. To keep the
pendulum balanced, the arm has to move back-and-forth and this is
why is oscillates about the offset angle.
5. Increase the Amplitude in the Dither Signal section by steps of 0.1 V until you notice a change in the arm angle
response.
6. K-1 From the Voltage (V) scope and the pendulum motion, what is the Dither signal doing? Compare the
response of the arm with and without the Dither signal.
Answer 4.6
Outcome
K-1
Solution
The Dither signal applied a sinusoidal voltage signal to the motor. This
is added to the balance control signal. Adding the Dither reduces the
amount of arm oscillation. For example, without the Dither the arm would
oscillate between -25 and 40 degrees. When adding a Dither with 3.50
V at 2.50 Hz the arm would oscillate between -5 and -13 degrees.
7. Increase the Frequency in the Dither Signal section starting from 1.00 to 10.0 Hz.
8. B-7 How does this effect the pendulum arm response?
Answer 4.7
Outcome
B-7
Solution
In general, increasing the frequency minimizes the amount the arm oscillation about a certain angle. For example, the arm will tend to move
back-and-forth more with a Dither of 3.0 V at 1.0 Hz then with a Dither
of 3.0 V at 2.5 Hz. However, increasing the Dither frequency too much
causes the pendulum arm to vibrate without improving the swing that
much.
9. B-9 Set the Dither Signal properties according to the friction measured in Section 2.4. How does this effect
the pendulum arm response?
QNET ROTPENT Laboratory Manual - Instructor Manual
22
Answer 4.8
Outcome
B-9
Solution
By using the identified Coulomb friction, the oscillatory arm angle response should be minimized optimally.
10. Click on the Stop button to stop running the VI.
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5
SWING-UP CONTROL
5.1 Background
5.1.1 Energy Control
If the arm angle is kept constant and the pendulum is given an initial position it would swing with constant amplitude.
Because of friction there will be damping in the oscillation. The purpose of energy control is to control the pendulum
in such a way that the friction is constant. The potential energy of the pendulum is
Ep = Mp g lp (1 − cos α)
(5.1)
and the kinetic energy is
Ek =
1
Jp α̇2 .
2
(5.2)
The potential energy is zero when the pendulum is at rest at α = 0 in Figure 2.2, and equals 2Mp g lp when the
pendulum is upright at α = ±π. The sum of the potential and kinetic energy of the pendulum is
E=
1
Jp α̇2 + Mp g lp (1 − cos α) .
2
(5.3)
Differentiating 5.3 results in the differential equation
(
)
Ė = α̇ Jp α̈2 + Mp g lp sin α .
(5.4)
Substituting the pendulum equation of motion given in Equation 2.1 for pendulum acceleration into Equation 5.4
gives
Ė = Mp u lp α̇ cos α.
Since the acceleration of the pivot is proportional to current driving the arm motor and thus also proportional to the
drive voltage we find that it is easy to control the energy of the pendulum. The proportional control law
u = (Er − E) α̇ cos α
(5.5)
drives the energy towards the reference energy Er . Notice that the control law is nonlinear because the proportional
gain depends on the pendulum angle, α. Also, notice that the control changes sign when α̇ changes sign and when
the angle is ± 90 deg.
However, for energy to change quickly the magnitude of the control signal must be large. As a result the following
swing-up controller is implemented in the LabVIEW VI
u = satumax (µ(Er − E)sign(α̇ cos α))
(5.6)
where µ is a tunable control gain and the satumax function saturates the control signal at the maximum acceleration
of the pendulum pivot, umax .
See Wikipedia for more information on potential energy, kinetic energy, control theory, and nonlinear control.
5.1.2 Hybrid Swing-Up Control
The energy swing-up control in 5.5 (or 5.6 can be combined with the balancing control law in 4.1 to obtain a control
law which performs the dual tasks of swinging up the pendulum and balancing it. As illustrated in Figure 5.1, this
can be accomplished by switching between the two control systems.
QNET ROTPENT Laboratory Manual - Instructor Manual
24
Figure 5.1: Swing-up hybrid control
This system can be modeled as a hybrid system. Hybrid systems are systems with both continuous and discrete
parts. There are two continuous part: the closed-loop system using the swing-up energy controller and the closedloop system using the PD balance controller. The switching strategy is the discrete element that chooses which
controller, or system, to run. The switching logic can be obtained by determining a region in state space where the
balancing works well. Balancing control is then used inside this region and energy control is used outside the region.
Figure 5.2 is a called a hybrid automaton and, for this specific task, can be used to describe the system model and
the switching logic.
Figure 5.2: Hybrid swing-up controller automaton
The circles in Figure 5.2 are called locations and represent the two different continuous system. The arrows are
called edges and represent the discrete jumps taken when certain condition are satisfied. The angle used in the
switching logic in Figure 5.2 is called the upright angle. It is defined as zero when the pendulum is about its upright
vertical position and expressed mathematically using
αup = α mod 2π − π.
The various switching parameters shown in Figure 5.2 can then be set as:
ϵ
= 2 deg
η
γ
= 720 deg/s
= 30 deg
Given that the pendulum starts in the downward vertical position, it is in the swing-up location of the hybrid automaton.
The swing-up controller pumps energy into the pendulum until it swings within ± 2 deg of its upright vertical position.
Once the pendulum is within that that range and does not exceed 720 deg/s in either direction, the edge is taken to
engage the balance controller. It remain in the Balance PD control location until the pendulum goes beyond the ±
30 deg position range or beyond ± 720 deg/s.
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5.2 Swing-Up Control VI
The virtual instrument used to run the swing-up controller on the QNET rotary pendulum system is the same as the
balance control given in Section 4.2 shown in Figure 4.1.
5.3 Energy Control [30 min]
1. Open the QNET ROTPENT Swing Up Control.vi and ensure it is configured as described in Section 6. Make
sure the correct Device is chosen.
2. Run the QNET ROTPENT Swing Up Control.vi. The VI should appear similarity as shown in Figure 4.1.
3. In the Balance Control Parameters section ensure the following parameters are set:
• kp theta = -6.50 V/rad
• kp alpha = 80.0 V/rad
• kd theta = -2.75 V/(rad/s)
• kd alpha = 10.5 V/(rad/s)
4. In the Swing-Up Control Parameters section set:
• mu = 55 m/s2 /J
• Er = 20.0 mJ
• max accel = 10 m/s2
• Activate Swing-Up = OFF (de-pressed)
5. Adjust the Angle/Energy (deg/mJ) scope scales to see between -250 and 250 (see the ROTPEN User Manual
([2]) for help).
6. Manually rotate the pendulum at different levels and examine the blue Pendulum Angle (deg) and the green
Pendulum Energy (mJ) in the Angle/Energy (deg/mJ) scope. The pendulum energy is also displayed numerically in the Control Indicators section.
7. B-5, K-1 What do you notice about the energy when the pendulum is moved at different positions? Record
the energy when the pendulum is being balanced (i.e., fully inverted in the upright vertical position).
Answer 5.1
Outcome
B-5
K-1
Solution
If they followed the procedure correctly, they should be able to perform
the following analyssi as well as measure the energy.
The pendulum energy increases proportionally with the pendulum angle.
When being balanced, the energy read is 81.0 mJ.
8. Click on the Stop button to bring the pendulum down to the gantry position and re-start the VI.
9. In the Swing-Up Control Parameters section, turn ON the Activate Swing-Up switch (the pressed down position).
10. If the pendulum is not moving, click on the Disturbance button in the Signal Generator section to perturb the
pendulum.
11. B-7, K-2 In Swing-Up Control Parameters, change the reference energy Er between 5.0 mJ and 50.0 mJ. As
it is varied, examine the control signal in the Voltage (V) scope as well as the blue Pendulum Angle (deg) and
the red Pendulum Energy (mJ) in the Angle/Energy (deg/mJ) scope. Attach the response of the Angle/Energy
(deg/mJ) and Voltage (V) scopes.
QNET ROTPENT Laboratory Manual - Instructor Manual
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Answer 5.2
Outcome
B-7
Solution
The larger the reference energy, the large the amplitude of the control
signal.
The responses shown in Figure 5.3 are using energy control with mu =
55 m/s2 /J and Er = 50 mJ, and max accel = 10 m/s2 .
K-2
(a) Rotary Arm, Pendulum Angle, and Energy
(b) Motor Voltage
Figure 5.3: Pendulum response using energy control with Er = 50 mJ.
12. B-7 In Control Parameters fix Er to 20.0 mJ and vary the swing-up control gain mu between 10 and 100
m/s2 /J. Describe how this changes the performance of the energy control.
Answer 5.3
Outcome
B-7
Solution
As the mu gain increases the amplitude of the pendulum swings become larger. Recall from swing-up controller given in 5.6, which is implemented in the VI, that µ is the proportional gain.
13. Click on the Stop button to stop running the VI.
5.4 Hybrid Swing-Up Control [20 min]
1. Open the QNET ROTPENT Swing Up Control.vi and ensure it is configured as described in Section 6. Make
sure the correct Device is chosen.
2. Run the QNET ROTPENT Swing Up Control.vi. The VI should appear similarity as shown in Figure 4.1.
3. In the Balance Control Parameters section ensure the following parameters are set:
• kp theta = -6.50 V/rad
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• kp alpha = 80.0 V/rad
• kd theta = -2.75 V/(rad/s)
• kd alpha = 10.5 V/(rad/s)
4. In the Swing-Up Control Parameters section set:
• mu = 55 m/s2 /J
• Er = 20.0 mJ
• max accel = 10 m/s2
• Activate Swing-Up = OFF (de-pressed)
5. Adjust the Angle/Energy (deg/mJ) scope scales to see between -250 and 250 (see the ROTPEN User Manual
([2] for help).
6. Make sure the pendulum is hanging down motionless and the encoder cable is not interfering with the pendulum.
7. In the Swing-Up Control Parameters, set the Activate Swing-Up switch to ON (pressed down position).
8. The pendulum should begin going back and forth. If not, click on the Disturbance button in the Signal Generator
section to perturb the pendulum. Turn off the Active Swing-Up switch if the pendulum goes unstable or
if the encoder cable interferes with the pendulum arm motion.
9. B-5 Gradually increase the reference energy Er in the Control Parameters section until the pendulum swings
up to the vertical position.
Answer 5.4
Outcome
B-5
Solution
Setting the reference energy, Er , between 80 and 85 mJ should be adequate to swing-up the pendulum to its vertical position.
10. B-9 What reference energy was required to swing-up the pendulum? Was this value expected?
Answer 5.5
Outcome
B-9
Solution
Between 80 and 85 mJ. This is inline with the potential energy of the
pendulum that was measured in Step 7 in Section 5.3 when the pendulum is vertically upwards.
11. Click on the Stop button to stop running the VI.
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6
SYSTEM REQUIREMENTS
Required Hardware
• NI ELVIS II (or NI ELVIS I)
• Quanser QNET Rotary Inverted Pendulum Trainer (ROTPENT). See QNET ROTPENT User Manual ([2]).
Required Software
• NI LabVIEWr 2010 or later
• NI LabVIEWr Control Design and Simulation Module
• ELVIS II Users: NI ELVISmx (installs required NI DAQmx drivers)
• ELVIS I Users:
– NI DAQmx
– ELVIS CD 3.0.1 or later installed
Caution: If these are not all installed then the VI will not be able to run! Please make sure all the software and
hardware components are installed. If an issue arises, then see the troubleshooting section in the QNET ROTPENT
User Manual ([2]).
6.1 Overview of Files
File Name
QNET ROTPENT User Manual.pdf
QNET ROTPENT
dent).pdf
Workbook
(Stu-
QNET ROTPENT Simple Modeling.vi
QNET ROTPENT Control Design.vi
QNET ROTPENT Swing Up Control.vi
QNET DCMCT Workbook (Instructor).pdf
Description
This manual describes the hardware of the QNET Rotary
Pendulum Trainer system and how to setup the system on
the ELVIS.
This laboratory guide contains pre-lab questions and lab
experiments demonstrating how to design and implement
controllers on the QNET DCMCT system LabVIEWr .
Apply voltage to DC motor and examine the arm and pendulum responses.
Design and simulate LQR-based balance controller.
Swing-up and balance pendulum.
Same as the student version except it includes the exercise solutions.
Table 2: Instructor design files supplied with the QNET ROTPENT Laboratory.
6.2 Simple Modeling Laboratory VI
The QNET-ROTPENT Simple Modeling VI is shown in Figure 6.1. It runs the DC motor connected to the pendulum
arm in open-loop and plots the corresponding pendulum arm and link angles as well as the applied input motor
voltage. Table 3 lists and describes the main elements of the ROTPENT Simple Modeling virtual instrument front
panel. Every element is uniquely identified through an ID number and located in Figure 6.1.
QNET ROTPENT Laboratory Manual - Instructor Manual
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Figure 6.1: QNET-ROTPENT Simple Modeling virtual instrument.
6.3 Control Design VI
The QNET ROTPENT Control Design VI enables users to design a balance controller and simulate its response.
The matrices for the state-space model of the rotary inverted pendulum system is shown in the Symbolic Model
tab and illustrated in Figure 6.2. The values of the variables used in the state-space model can be changed. In
the Open Loop Analysis tab, shown in Figure 6.3, the numerical state-space model is displayed and the resulting
open-loop poles are plotted on a phase plane. Based on this model, a controller to balance the rotary inverted
pendulum system can be designed using the Linear-Quadratic Regulator (LQR) optimization technique, as shown
in the Simulation tab in Figure 6.4. The resulting closed-loop inverted pendulum system can be simulated. Table
4 lists and describes the main elements of the ROTPENT Control Design virtual instrument user interface. Every
element is uniquely identified through an ID number and located in figures 6.2, 6.3, and 6.4.
6.4 Swing-Up Control VI
The QNET Rotary Pendulum Trainer Swing-Up Control VI implements an energy-based control that swings up the
pendulum to its upright vertical position and a state-feedback controller to balance the pendulum when in its upright
position. The main elements of the VI front panel are summarized in Table 5 and identified in Figure 6.5 through the
corresponding ID number.
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30
ID #
1
Label
Theta
Symbol
θ
2
Alpha
α
3
4
5
Current
Voltage
Signal Type
Im
Vm
6
7
8
9
10
11
12
13
Amplitude
Frequency
Offset
Disturbance
Device
Sampling Rate
Stop
Scopes: Angle
14
Scopes: Voltage
Vsd
θ, α
Vm
Description
Arm angle numeric display measured by
encoder on motor.
Pendulum angle numeric display measured by encoder on pendulum pivot.
Motor armature current numeric display.
Motor input voltage numeric display.
Type of signal generated for the input
voltage signal.
Generated signal amplitude input box.
Generated signal frequency input box.
Generated signal offset input box.
Apply simulated disturbance voltage.
Selects the NI DAQ device.
Sets the sampling rate of the VI.
Stops the LabVIEW VI from running.
Scope with measured arm angle (in red)
and pendulum angle (in blue).
Scope with applied motor voltage (in
red).
Unit
deg
deg
A
V
V
Hz
V
V
Hz
deg
V
Table 3: QNET ROTPENT Simple Modeling VI Components
Figure 6.2: QNET ROTPENT Control Design VI: Symbolic Model tab.
QNET ROTPENT Laboratory Manual - Instructor Manual
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Figure 6.3: QNET ROTPENT Control Design VI: Open Loop Analysis tab.
Figure 6.4: QNET ROTPENT Control Design VI: Simulationtab.
QNET ROTPENT Laboratory Manual - Instructor Manual
32
ID #
1
2
Label
Mp
lp
Symbol
Mp
lp
3
4
5
r
Jp
Jeq
r
Jp
Jeq
6
7
Bp
Beq
Bp
Beq
8
9
10
Kt
Km
Rm
Kt
Km
Rm
11
12
13
14
15
16
17
A
B
C
D
18
Symbolic A
Symbolic B
Symbolic C
Symbolic D
Stop
Error Out
Open-Loop Equation
Pole-Zero Map
19
Signal Type
20
21
22
23
24
Amplitude
Frequency
Offset
Disturbance
Q
Vsd
Q
25
R
R
26
Optimal Gain (K)
K
27
Arm
θ
28
29
Pendulum
Control Input
α
Vm
Description
Mass of pendulum assembly (link + weight).
Center of mass of pendulum assembly
(link+weight) input box.
Length from motor shaft to pendulum pivot.
Pendulum moment of inertia relative to pivot.
Equivalent moment of inertia acting on the DC
motor shaft.
Viscous damping about the pendulum pivot.
Equivalent viscous damping acting on the DC
motor shaft.
DC motor current-torque constant.
DC motor back-emf constant.
Electrical resistance of the DC motor armature.
Rotary pendulum linear state-space matrix A.
Rotary pendulum linear state-space matrix B.
Rotary pendulum linear state-space matrix C.
Rotary pendulum linear state-space matrix D.
Stops the LabVIEW VI from running.
Displays any error encountered in the VI.
Numeric linear state-space model of rotary
pendulum.
Maps pole and zeros of open-loop rotary pendulum system.
Type of signal generated for the arm position
reference.
Generated signal amplitude input box.
Generated signal frequency input box.
Generated signal offset input box.
Apply simulated disturbance voltage.
Linear-quadratic weighting matrix that defines
a penalty on the state.
Linear-quadratic weighting matrix that defines
a penalty on the control action.
State-feedback control gain calculated using
LQR.
Scope with reference (in blue) and measured
(in red) arm angles.
Scope with inverted pendulum angle (in blue).
Scope with applied motor voltage (in red).
Unit
kg
m
m
kg.m2
kg.m2
N.m.s/rad
N.m.s/rad
N.m/A
V.s/rad
Ω
V
Hz
V
V
deg
deg
V
Table 4: QNET ROTPENT Control Design VI Components
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Figure 6.5: QNET ROTPENT Swing-Up Control VI.
QNET ROTPENT Laboratory Manual - Instructor Manual
34
ID #
1
Label
Theta
Symbol
θ
2
Alpha
α
3
4
Current
In Range?
Im
5
6
Energy
Signal Type
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Amplitude
Frequency
Offset
Disturbance
Amplitude
Frequency
Offset
kp theta
kp alpha
kd theta
kd alpha
mu
Er
Max accel
Activate Swing Up
22
23
Mp
lp
Mp
lp
24
25
26
27
Marm
r
Jp
Jeq
Marm
r
Jp
Jeq
28
29
Kt
Rm
Kt
Rm
30
31
32
33
Device
Sampling Rate
Stop
Scopes: Angle
θ, α
34
Scopes: Voltage
Vm
Vsd
Ad
fd
Vd0
kp,θ
kp,α
kd,θ
kd,α
µ
Er
umax
Description
Arm angle numeric display measured by encoder on motor.
Pendulum angle numeric display measured
by encoder on pendulum pivot.
Motor armature current numeric display.
Balance controller is engaged when this LED
is turns bright green.
Numeric display of the pendulum energy.
Type of signal generated for the arm reference signal (i.e., desired angle of arm).
Reference position amplitude input box.
Reference position frequency input box.
Reference position offset input box.
Apply simulated disturbance voltage.
Dither signal amplitude input box.
Dither signal frequency input box.
Dither signal offset input box.
Arm angle proportional gain input box.
Pendulum angle proportional gain input box.
Arm angle derivative gain input box.
Pendulum angle derivative gain input box.
Proportional gain for energy controller.
Reference energy for energy controller.
Maximum acceleration
When pressed down the energy controller that
swings-up the pendulum is engaged.
Mass of pendulum assembly (link + weight).
Center of mass of pendulum assembly
(link+weight) input box.
Mass of rotary arm.
Length from motor shaft to pendulum pivot.
Pendulum moment of inertia relative to pivot.
Equivalent moment of inertia acting on the DC
motor shaft.
DC motor current-torque constant.
Electrical resistance of the DC motor armature.
Selects the NI DAQ device.
Sets the sampling rate of the VI.
Stops the LabVIEW VI from running.
Scope with measured arm angle (in red) and
pendulum angle (in blue).
Scope with applied motor voltage (in red).
Unit
deg
deg
A
mJ
deg
Hz
deg
V
V
Hz
V
V/rad
V/rad
V.s/rad
V.s/rad
m/(s2.J)
mJ
m/s2
kg
m
kg
m
kg.m2
kg.m2
N.m/A
Ω
Hz
deg
V
Table 5: QNET ROTPENT Swing-Up Control VI Components
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7
LAB REPORT
This laboratory contains three groups of experiments, namely,
1. Modeling,
2. Balance control design
3. Balance control implementation
4. Swing-up control
For each experiment, follow the outline corresponding to that experiment to build the content of your report. Also,
in Section 7.5 you can find some basic tips for the format of your report.
7.1 Template for Content (Simple Modeling)
I. PROCEDURE
1. Damping
• Briefly describe the main goal of the experiment.
• Briefly describe the experiment procedure in Step 6 in Section 2.3.
2. Friction
• Briefly describe the main goal of the experiment.
• Briefly describe the experiment procedure in Step 5 in Section 2.4.
3. Moment of Inertia
• Briefly describe the main goal of the experiment.
• Briefly describe the experiment procedure in Step 4 in Section 2.5.
II. RESULTS
Do not interpret or analyze the data in this section. Just provide the results.
1. Provide applicable data collected in this laboratory from Table 1.
III. ANALYSIS
Provide details of your calculations (methods used) for analysis for each of the following:
1. Damping analysis in step 6 in Section 2.3.
2. Finding friction in step 5 in Section 2.4.
3. Calculating moment of inertia of pendulum in step 4 in Section 2.5.
IV. CONCLUSIONS
Interpret your results to arrive at logical conclusions for the following:
1. How well does the experimentally derived moment of inertia compare with analytically derived value in step 5
of Section 2.5.
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7.2 Template for Content (Balance Control Design)
I. PROCEDURE
1. Model Analysis
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 6 in Section 3.3.
2. Control Design and Simulation
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 6 in Section 3.4.
II. RESULTS
Do not interpret or analyze the data in this section. Just provide the results.
1. LQR matrices and control gain found in Step 9 in Section 3.4.
2. Simulated closed-loop response plot from Step 10 in Section 3.4.
III. ANALYSIS
Provide details of your calculations (methods used) for analysis for each of the following:
1. Open-loop poles in Step 6 in Section 3.3.
2. Effect of changing moment of inertia on open-loop poles in Step 8 in Section 3.3.
3. Effect of changing LQR elements on response in Step 6 in Section 3.4.
4. Effect of changing different LQR element on the response in Step 8 in Section 3.4.
IV. CONCLUSIONS
Interpret your results to arrive at logical conclusions for the following:
1. Does lowering the moment of inertia of the pendulum have the expected result Step 8 in Section 3.3.
2. Does the simulation match the specifications in Step 10 in Section 3.4.
QNET ROTPENT Laboratory Manual - Instructor Manual
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7.3 Template for Content (Balance Control Implementation)
I. PROCEDURE
1. Default Balance Control
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 8 in Section 4.3.
2. Implement Designed Balance Control
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 7 in Section 4.4.
3. Balance Control with Friction Compensation
• Briefly describe the main goal of this experiment.
• Briefly describe the experimental procedure in Step 4 in Section 4.5.
II. RESULTS
Do not interpret or analyze the data in this section. Just provide the results.
1. Balance control response plot from step 7 in Section 4.4.
III. ANALYSIS
Provide details of your calculations (methods used) for analysis for each of the following:
1. Effect of changing offset in Step 8 in Section 4.3.
2. Balance control analysis in Step 9 in Section 4.3.
3. Balance control analysis when tracking step reference in 11 in Section 4.3.
4. Examining the arm oscillation in Step 4 in Section 4.5.
5. Explain what the Dither signal is doing in Step 6 in Section 4.5.
6. Effect of increasing Dither signal frequency in Step 8 in Section 4.5.
IV. CONCLUSIONS
Interpret your results to arrive at logical conclusions for the following:
1. Whether the balance controller meets the specifications in Step 7 in Section 4.4.
2. Effect of setting the Dither signal to the identified friction parameters in Step 9 of Section 4.5.
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7.4 Template for Content (Swing-Up Control)
I. PROCEDURE
1. Energy Control
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 7 in Section 5.3.
2. Hybrid Swing-Up Control
• Briefly describe the main goal of the experiment.
• Briefly describe the experimental procedure in Step 9 in Section 5.4.
II. RESULTS
Do not interpret or analyze the data in this section. Just provide the results.
1. Pendulum response from Step 11 in Section 5.3.
III. ANALYSIS
Provide details of your calculations (methods used) for analysis for each of the following:
1. Energy at different pendulum position in Step 7 in Section 5.3.
2. Effect of changing reference energy in Step 11 in Section 5.3.
3. Effect of changing proportional gain in Step 11 in Section 5.3.
IV. CONCLUSIONS
Interpret your results to arrive at logical conclusions for the following:
1. Reference energy required to swing-up pendulum in Step 10 of Section 5.4.
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7.5 Tips for Report Format
PROFESSIONAL APPEARANCE
• Has cover page with all necessary details (title, course, student name(s), etc.)
• Each of the required sections is completed (Procedure, Results, Analysis and Conclusions).
• Typed.
• All grammar/spelling correct.
• Report layout is neat.
• Does not exceed specified maximum page limit, if any.
• Pages are numbered.
• Equations are consecutively numbered.
• Figures are numbered, axes have labels, each figure has a descriptive caption.
• Tables are numbered, they include labels, each table has a descriptive caption.
• Data are presented in a useful format (graphs, numerical, table, charts, diagrams).
• No hand drawn sketches/diagrams.
• References are cited using correct format.
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8
SCORING SHEETS
8.1 Simple Modeling: Pre-Lab Questions
Student Name :
Question1
A-1
A-2
A-3
1
Total
.
1 This
scoring sheet is for the Simple Modeling Pre-Lab questions in Section 2
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8.2 Simple Modeling Lab Report
Student Name:
K-1
Item1
I. PROCEDURE
B-5
CONTENT
B-6
B-7
B-9
FORMAT
GS-1
GS-2
I.1. Damping
1
I.2. Friction
2
I.3. Moment of Inertia
3
II. RESULTS
1
III. ANALYSIS
1
2
3
IV. CONCLUSIONS
1
Total
1 This
scoring sheet corresponds to the report template in Section 7.1.
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8.3 Balance Control Design: Lab Report
Student Name:
K-1
Item1
I. PROCEDURE
K-2
CONTENT
K-3
B-5
B-7
B-9
FORMAT
GS-1
GS-2
I.1. Model Analysis
1
I.2. Control Design and Simulation
2
II. RESULTS
1
2
III. ANALYSIS
1
2
3
4
IV. CONCLUSIONS
1
2
Total
1 This
scoring sheet corresponds to the report template in Section 7.2.
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8.4 Balance Control Implementation: Lab Report
Student Name:
K-1
Item1
I. PROCEDURE
K-2
CONTENT
B-5
B-7
B-8
B-9
FORMAT
GS-1
GS-2
I.1. Default Balance Control
1
I.2. Implement Designed Balance Control
2
I.3. Balance Control with Friction Compensation
3
II. RESULTS
1
III. ANALYSIS
1
2
3
4
5
6
IV. CONCLUSIONS
1
Total
1 This
scoring sheet corresponds to the report template in Section 7.3.
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8.5 Swing-Up Control: Lab Report
Student Name:
K-1
Item1
I. PROCEDURE
K-2
CONTENT
B-5
B-7
B-9
FORMAT
GS-1
GS-2
I.1. Energy Control
1
I.2. Hybrid Swing-Up Control
2
II. RESULTS
1
III. ANALYSIS
1
2
3
IV. CONCLUSIONS
1
Total
1 This
scoring sheet corresponds to the report template in Section 7.4.
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Appendix A
QNET Instructor's Guide
Every laboratory in this manual is organized into four parts:
Background section provides all the necessary theoretical background for the experiments. Students should read
this section first to prepare for the Pre-Lab questions and for the actual lab experiments.
Virtual Instrument introduces the LabVIEWr Virtual Instrument that is to be used for the lab experiment.
Lab Experiments section provides step-by-step instructions to conduct the lab experiments and to record the collected data. The lab may also include a set of pre-lab questions that need to be done prior to the lab experiments.
System Requirements section describes all the details of how to configure the hardware and software to conduct
the experiments. It is assumed that the hardware and software configuration have been completed by the instructor
or the teaching assistant prior to the lab sessions. However, if the instructor chooses to, the students can also
configure the systems by following the instructions given in this section.
Assessment of ABET outcomes is incorporated into this manual as shown by indicators such as A-1, A-2 . These
indicators correspond to specific performance criteria for an outcome.
A.1 Pre-lab Questions and Lab Experiments
A.1.1
How to use the pre-lab questions
All or some of the questions in the Pre-Lab Questions sections can be assigned to students as homework. One
possibility is to assign them as a homework one week prior to the actual lab session and ask the students to bring
their assignment to the lab session. This would help them get ready for the lab session. You should encourage
them to study the background section of the chapter prior to attempting the pre-lab questions. Note that solutions
for some of the Pre-Lab questions are parameters needed for the experiments in the lab session.
Another possibility is to go over some of these questions either in class or in the lab session together with the
students. This could generate an interactive learning opportunity for them prior to the lab.
Finally, it is possible to use some of the pre-lab questions in your mid-term or final exams. This would reinforce the
concepts covered in the labs; connections between the abstract theory and the real hardware; and would give you
an option to integrate some of the work done in the lab sessions into your exams.
A.1.2
How to use the laboratory experiments
This manual is organized into several laboratory sections. Each section contains several experiments which are,
for the most part, independent of each other. Therefore, one possible way to use this material is to conduct the
individual experiments in your weekly lab sessions. Another possibility is to divide the class into teams and have
each team conduct an experiment given in a section.
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A.2 Assessment for ABET Accreditation
In the United States, accreditation is a peer-review process. Educational institutions or programs volunteer to undergo this review periodically to determine if certain criteria are being met. The Accreditation Board for Engineering
and Technology, ABET, is responsible for the specialized accreditation of educational programs in applied science,
computing, engineering, and technology. ABET accreditation is assurance that a college or university program
meets the quality standards established by the profession for which it prepares its students.
It is the responsibility of the program seeking accreditation to demonstrate clearly that the program meets a set of
criteria. One of these criteria is the ``Criterion 3: Program Outcomes''. Engineering programs must demonstrate
that their students attain program outcomes (a) through (k). Much more information about this can be found in the
``Criteria for Engineering Accreditation'' document ABET publishes on its website annually (http://www.abet.org).
For fulfillment of Criterion 3, a program must show that there is an assessment and evaluation process in place that
periodically documents and demonstrates the degree to which the program outcomes are attained by their students.
Most programs do this by mapping the outcomes (a) through (k) to the courses in the curriculum1 . Then, these
outcomes are assessed in the courses. Finally, the assessment results are collected from the courses and compiled
into program-level data to demonstrate the ``degree to which the program outcomes are attained by their students''.
If your course is part of a similar assessment effort in your program, you probably need to assess the following
outcomes in your course:
(A) An ability to apply knowledge of mathematics, science, and engineering,
(B) An ability to design and conduct experiments, as well as to analyze and interpret data,
(G) An ability to communicate effectively, and
(K) An ability to use the techniques, skills, and modern engineering tools necessary for engineering practice.
These outcomes can be assessed in your course using various assessment tools, such as student surveys and
assignments or questions targeting specific outcomes. To measure achievement of an outcome (such as outcome
``A'' in the list above), typically some performance criteria are defined for the outcome. The performance criteria
are a set of measurable statements to define each learning outcome. They identify the specific knowledge, skills,
attitudes, and/or behavior students must demonstrate as indicators of achieving the outcome.
For the purpose of this laboratory curriculum, we defined a set of performance criteria for each outcome. These
criteria are labeled as ``A-1, A-2, B-3, ..., K-3'' as indicated in the rubrics in Section A.3 below. We also embedded
these performance criteria in the curriculum shown by indicators such as A-1, A-2 .
A.2.1
Assessment in your course
Assessment of outcomes is different than grading. A course grade (or a grade on an assignment or exam), is a
composite indicator. For example, if a student receives "B" as a grade in your course, it is probably difficult to tell
his/her level of achievement in outcome "A" versus "G". One of the purposes of assessment is to "measure" the level
of achievement of these specific skills and knowledge so that improvements can be made in the future offerings of
the course.
So, how should you introduce outcomes assessment into your course? The outcomes assessment approach
described here can be applied to each pre-lab homework assignment and lab report of each student throughout the
semester. This may or may not be feasible depending on your class size. In general, a representative sample of
student work is assessed.
You can continue to give assignments/exams and grade them in the traditional way. To introduce assessment into
your course, you can pick a representative sample of student work and "score" their work using the scoring sheets
and rubrics given in this manual. This is a good way to start introducing assessment into your course.
1 Disclaimer:
The opionions expressed or the assessment techniques described here have not been endorsed by ABET in any way.
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Recall that for fulfillment of Criterion 3, a program must ``document'' the assessment process. Programs collect sample student work in the academic year prior to the site visit by an ABET team. You can retain the sample homeworks,
lab reports, their scoring sheets and the assessment workbook as ``evidence'' for the ongoing assessment effort in
your course. This collection can then be given to the assessment committee in your program to be incorporated into
the program-level evidence they will compile prior to the ABET site visit.
A.2.2
How to score the pre-lab questions
If you choose to assign the pre-lab questions as homework, then the outcome targetted by these questions can be
assessed using the student work. The pre-lab questions require students to ``apply'' their math and engineering
science knowledge through calculations and problem solving strategies. Therefore, outcome ``A'' was mapped to
the pre-lab questions through its performance criteria.
If you assign the pre-lab questions as homework, you can ``score'' the returned homeworks using the rubric for
outcome ``A'' given in Section A.3 and the scoring sheet provided for that pre-lab in that chapter.
To score homework of one student:
1. Print the scoring sheet for the Pre-Lab Questions section you assigned as homework. One sheet is used per
student.
2. Use the rubric for ``Outcome A'' (Section A.3) to assign a score for each question. The rubric gives the description of ``levels of achievement'' (4 = exemplary, 3 = proficient, 2 = developing and 1 = beginning/incomplete)
for each criterion. As an example, below is a completed sample scoring sheet after evaluating the homework
of one student.
Question
A-1
A-2
1
3
2
2
4
2
3
3
4
3
5
4
6
3
7
3
8
9
A-3
3
3
3
10
3
4
11
3
4
32
8
Total
10
3. You can then enter the ``Total'' for each performance criterion into the assessment workbook [1] as shown in
Figure A.1.
A.2.3
How to score the lab reports
As mentioned earlier in Section A.1.2, there are various ways in which you can use the material provided in this
manual. In any case, the outcomes targetted by the lab experiments can be assessed from the lab reports submitted
by the students. These reports should follow the specific template for content given at the end of each laboratory
chapter. This will provide a basis to assess the outcomes easily.
The lab activities correspond to the ``applied'' part of engineering. Therefore, outcomes ``B'' and ``K'' were mapped
to the lab activities through their performance criteria. The lab reports themselves match outcome ``G'' on effective
communication skills.
If you choose to do an individual experiment in your weekly lab sessio then you can ask the students to submit a lab
report using the report template provided for this experiment. The template contains the main ``content'' sections you
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Figure A.1: Pre-Lab entry into the assessment workbook for one student.
would expect in a typical lab report (procedure, results, analysis, conclusions). Each section of the report template
ties back to the activities in the lab and the corresponding assessment indicators. It also contains performance
criteria related to the ``format'' of the report.
You can score the lab reports using the rubric for outcome ``G'' given in Section A.3 and the scoring sheet provided for
the experiment in that section. Note that each lab report scoring sheet directly corresponds to the lab report content
template for that experiment. Also, note that the rubric for outcome ``G'' already contains rubrics for outcomes ``B''
and ``K'' since these outcomes appear as an integral part of the report.
To score the lab report of one student:
1. Print the scoring sheet for the Lab Report for the experiment they conducted in the lab. One sheet is used per
student.
2. Use the ``Content'' rubric (Section A.3) to assign a score for each entry in the scoring sheet. The rubric
gives the description of ``levels of achievement'' (4 = exemplary, 3 = proficient, 2 = developing and 1 = beginning/incomplete) for each criterion. As an example, below is a completed scoring sheet after evaluating the
lab report of one student.
3. Use the ``Format'' rubric (Section A.3) for the ``GS-1 and GS-2'' criteria to score the formatting of the report
on the same scoring sheet.
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K-1
Item1
I. PROCEDURE
K-2
CONTENT
B-5
B-6
B-7
B-9
FORMAT
GS-1
GS-2
I.1. Frequency Response Experiment
1
I.2. Bump Test Experiment
4
1
4
I.3. Model Validation Experiment
1
II. RESULTS
4
1
4
2
3
3
3
4
III. ANALYSIS
3
III.1. Frequency Response Experiment
1
2
2
3
III.2. Bump Test Experiment
1
3
IV. CONCLUSIONS
1
Total
6
10
12
3
2
3
3
4
3
4. You can then enter the ``Total'' for each performance criterion into the assessment workbook [1] as show in
Figure A.2.
Figure A.2: Lab report score entries in the workbook for one student.
A.2.4
Assessment of the outcomes for the course
As explained earlier, the performance criteria, such as A-1, A-2, A-3, are used to describe a set of measurable
statements to define each learning outcome. Up to this point, we explained how to assess each performance
criterion using the pre-labs, the lab reports and the scoring sheets.
A single score for each outcome can be computed to indicate the level of attainment of that outcome by the entire
class. One approach is to simply average the scores for the performance criteria for that outcome. For example, in
case of outcome ``A'', you can use:
SCOREA =
SCOREA−1 + SCOREA−2 + SCOREA−3
3
(A.1)
Another possibility is to use a weighted-average where some of the performance criteria are considered to be more
important than the others. In case of outcome ``A'', you can use:
w1 · SCOREA−1 + w2 · SCOREA−2 + w3 · SCOREA−3
(A.2)
w1 + w2 + w3
where w1 , w2 and w3 are weights you can assign (on the 0 to 1 scale) for the performance criteria A-1, A-2 and A-3,
respectively. The total of all weights should equal 1.
SCOREA =
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A.2.5
Course Score for outcome A
The assessment workbook [1] incorporates the simple average approach as shown in Figure A.3.
Figure A.3: Computation of single score for outcome ``A'' in the assessment workbook.
A.2.6
Course Scores for outcomes B, K and G
Similarly, the simple average approach is also used for outcomes B, K and G. Referring to the rubrics in Section A.3,
it should be noted that outcome ``G'' contains performance criteria for both ``B'' and ``K'' to assess the content of
the report. In addition, there are two performance criteria, GS-1 and GS-2, to assess the format of the report. The
scores for all of these performance criteria are averaged to arrive at the single score for outcome G. For example,
the single score for outcome G in Figure A.4 for the Modelling experiment was calculated using:
SCOREG = AV ERAGE(SK−1 + SK−2 + SB−5 + SB−6 + SB−7 + SB−9 + SGS−1 + SGS−2 )
(A.3)
where SK−1 · · · SGS−2 are the scaled average scores for K-1 through GS-2 in the workbook.
Figure A.4: Computation of single score for outcome ``G'' in the assessment workbook.
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A.2.7
Assessment workbook
The assessment workbook [1] was developed using Microsoft Excelr . It is intented to give a general idea for how
the assessment scores can be tracked and brought together. On purpose we designed the workbook to have no
automatic features. You can use it as is or customize it in any way you like.
The assessment workbook has a tab for the Pre-Lab Questions and a tab for each of the laboratory chapters. Only
10 students were listed assuming you would use samples of student work and not the entire class. If you want to
add more students, you can insert rows into the spreadsheets. Note: If you insert new rows, make sure that the
formula ranges in the cells with calculations are correct.
At the bottom of each pre-lab section, there is a row entitled ``Total Possible''. To count a pre-lab assignment in
the calculation of the overall scores, you need to enter the correct totals here. For example, to count the Pre-Lab
for modeling, you need to enter 12, 44 and 8 (Figure A.1). If you want to exclude an assignment from the overall
calculation, enter ``0'' as shown in Figure A.5. Of course, if you are excluding a pre-lab, then do not enter any scores
for the students under those columns.
Figure A.5: Enter ``0'' to exclude or ``correct totals'' to include a Pre-Lab assignment in the calculation of the overall
scores.
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Apply math, science and engineering
A.3 Rubrics
Code
Perf. Criteria
A-1
Has strategies
to solve the
problem
A-2
Performs
calculations
A-3
Explains results
4
Exemplary
3
Proficient
2
Developing
Uses a
sophisticated
strategy.
Employs refined
and complex
reasoning to
arrive at the
solution.
Arrived at
correct answer.
Calculations are
complete.
Precise math
language,
symbolic
notation, graphs
diagrams, etc.
are used.
Explains the
result in the
context of the
completed
calculations by
providing
complex
reasoning and
interpretations.
Clear logical
conclusions are
drawn.
Uses an
appropriate
strategy for
solution.
Content
knowledge is
used correctly.
Has a strategy
for solution but
content
knowledge has
some
conceptual
errors.
1
Beginning or
incomplete
Uses a wrong
strategy or there
is no evidence
of a strategy.
Content
knowledge has
many errors.
Arrived at
correct answer
with correct
calculations.
Arrived at
correct answer.
Calculations are
mostly correct
but there are
some minor
errors.
No answer or
arrived at wrong
answer.
Calculations are
mostly or
completely
wrong.
Explains the
result in the
context of the
completed
calculations.
Logical
conclusions are
drawn.
Some
explanation of
the result is
provided but it
does not
demonstrate
logical
reasoning.
There are no
explanations of
the result or an
attempt was
made to provide
an explanation
but it is
incomplete or
wrong.
Table 6: OUTCOME A: An ability to apply knowledge of mathematics, science, and engineering
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Design
Code Perf. Criteria
B-1
Identifies
pothesis
test
hyto
B-2
Identifies independent
and
dependent
variables
B-3
Lists assumptions made
B-4
Formulates experimental plan
to investigate a
phenomenon
4
Exemplary
3
Proficient
a
Framed
a Framed
testable ques- testable question
correctly tion correctly
and explained
the anticipated
cause-andeffect expectation leading to
the question
variables
All
variables All
identified
are
identified are
correctly, expla- correctly
nations
about
their
relations
are provided
All assumptions All assumptions
and their rea- are listed
sons are clearly
listed
Developed
a Developed corsophisticated
rect experimenexperimental procedure to
tal
procedure test the hypothcomplete with esis
details of every
step to test the
hypothesis
(Continued on the next page)
2
Developing
Framed a question that may
or may not be
testable
1
Beginning or
incomplete
Incomplete or
no
testable
question
Most variables
are
identified
correctly
None or only a
few
variables
are
identified
correctly
Assumptions
are listed but
some are missing
Attempted but
could not completely develop
an experimental
procedure
to
test the hypothesis
No assumptions
listed or most of
them are missing
Could
not
develop
an
accurate
experimental
procedure
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Code Perf. Criteria
Follows
experimental
procedures
B-6
Documents data
collected
B-7
Uses appropriate methods to
analyze data
B-8
Accounts
for
experimental
uncertainties
B-9
Interprets
results
with
respect to the
original hypothesis
Interpret
Analyze
Conduct
B-5
4
Exemplary
3
Proficient
2
Developing
1
Beginning or
incomplete
Follows
experimental
procedures
carefully
with
great
attention to detail.
Makes precise
measurements
Systematically
documents all
data in an exemplary
way
and by using
accurate units
Follows experimental procedures
leading
to correct measurements
Follows
experimental
procedures
with some mistakes leading to
mostly correct
measurements
Follows
experimental
procedures
with many mistakes leading to
mostly
wrong
measurements
Documents all
data and with
accurate units.
No data are
documented or
there are major
mistakes in the
units
Excellent,
indepth analysis
of the data using appropriate
methods
Is aware of
all
potential
experimental
errors and can
fully
account
for them with
suggestions to
improve them
Provides clear,
in-depth, accurate
explanations, including
trends,
and
arrives at logical
conclusions
based on data
and results
Appropriate
level of analysis
of data using
correct methods
Documents
data with some
mistakes in the
units or some
data
missing.
Data
organization
needs
improvement
Some data analysis but incomplete
Is aware of all
potential experimental errors
Is aware of
some of the
potential experimental errors
Is unaware of
any experimental errors
Provides accurate
explanations and logical
conclusions
based on data
and results
Provides explanations and conclusions but with
some errors
No explanation
or conclusions
are provided or
they are wrong
No analysis or
attempts to analyze with wrong
methods
Table 7: OUTCOME B: An ability to design and conduct experiments, as well as to analyze and interpret data.
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Code Perf. Criteria
B-1 Identifies
hypothesis
to test
Procedure
B-2
B-3
B-4
B-5
Identifies
independent
and
dependent
variables
Lists
assumptions
made
Formulates
experimental plan to
investigate
a
phenomenon
Follows experimental
procedures
4
Exemplary
3
Proficient
2
Developing
Framed a testable
question correctly
and
explained
the
anticipated
cause-and-effect
expectation leading
to the question
All variables are
identified correctly,
explanations about
their relations are
provided
All assumptions and
their reasons are
clearly listed
Developed a sophisticated experimental
procedure complete
with details of every
step to test the hypothesis
Framed a testable
question correctly
Framed a question
that may or may not
be testable
All variables are
identified correctly
Most variables are
identified correctly
None or only a few
variables are identified correctly
All assumptions are
listed
Assumptions
are
listed but some are
missing
Attempted but could
not
completely
develop an experimental procedure to
test the hypothesis
Could not develop
an accurate experimental procedure
Follows experimental procedures with
some mistakes leading to mostly correct
measurements
No
assumptions
listed or most of
them are missing
Developed correct
experimental
procedure to test the
hypothesis
Follows
experi- Follows experimenmental procedures tal procedures leadcarefully with great ing to correct meaattention to detail. surements
Makes
precise
measurements
(Continued on the next page)
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Beginning
or
incomplete
Incomplete or no
testable question
Follows experimental procedures with
many mistakes leading to mostly wrong
measurements
56
Results
Code Perf. Criteria
3
Proficient
2
Developing
1
Beginning
incomplete
Documents
data
with some mistakes
in the units or some
data missing. Data
organization needs
improvement
Can use software
tools for data presentation with only a
few mistakes
No data are documented or there are
major mistakes in
the units
Cannot use software
tools for simulation
or attempts to use
them but with many
mistakes
No analysis or attempts to analyze
with wrong methods
or
B-6
Documents
data
collected
Systematically documents all data in
an exemplary way
and by using accurate units
Documents all data
and with accurate
units.
K-2
Uses software tools
to present
data in useful
format
(graphs,
numerical, table,
charts,
diagrams)
Uses software tools
to simulate
physical
systems
Uses appropriate methods to analyze data
Accounts
for experimental
uncertainties
Can use various
software tools and
their advanced features correctly for
data presentation
Can use software
tools correctly for
data presentation
Can use software
tools and their advanced
features
correctly for simulation
Excellent, in-depth
analysis of the data
using
appropriate
methods
Is aware of all potential experimental errors and can fully account for them with
suggestions to improve them
Can use various
software tools and
their advanced features correctly for
analysis
Provides
clear,
in-depth, accurate
explanations,
including trends, and
arrives at logical
conclusions based
on data and results
Can use software
tools correctly for
simulation
Can use software
tools for simulation
with only a few
mistakes
Appropriate level of
analysis of data using correct methods
Some data analysis
but incomplete
Is aware of all potential experimental errors
Is aware of some of
the potential experimental errors
Is unaware of any
experimental errors
Can use software
tools correctly for
analysis
Can use software
tools for analysis
with only a few
mistakes
Provides accurate
explanations
and
logical conclusions
based on data and
results
Provides explanations and conclusions but with some
errors
Cannot use software
tools for analysis
or attempts to use
them but with many
mistakes
No explanation or
conclusions are provided or they are
wrong
K-3
B-7
Analysis
B-8
Conclusions
4
Exemplary
K-1
Uses software tools
for analysis
B-9
Interprets
results with
respect to
the original
hypothesis
Cannot use software tools for data
presentation
or
attempts to use
them but with many
mistakes (missing
labels, etc.)
Table 8: OUTCOME G: Ability to communicate effectively. (for Lab Report - CONTENT)
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Code
GS-1
GS-2
3
Proficient
2
Developing
• Each of the required sections is
completed.
• If necessary, subsections are used
• All necessary background principles and information for the experiment are given
• All grammar/spelling correct
• References are cited
Two of the
conditions
for the "exemplary"
category
were not met
Three of the
conditions
for the "exemplary"
category
were not met
1
Beginning or
incomplete
Four or none
of the conditions for the
"exemplary"
category
were not met
Professional • Has cover page with all necesappearsary details (title, course, student
ance
name(s), etc.)
• Typed
• Report layout is neat
• Does not exceed specified maximum page limit
• Pages are numbered
• Equations are consecutively numbered
• Figures are numbered, axes have
labels, each figure has a descriptive
caption
• Tables are numbered, they include
labels, each table has a descriptive
caption
• No hand drawn sketches/diagrams
• References are cited using correct
format
Two of the
conditions
for the "exemplary"
category
were not met
Four of the
conditions
for the "exemplary"
category
were not met
Five or more
of the conditions for the
"exemplary"
category
were not met
Perf.
Criteria
Content
presentation
well organized
4
Exemplary
Table 9: OUTCOME G: Ability to communicate effectively. (for Lab Report - FORMAT)
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Use techniques, skills and modern eng. tools
Code Perf. Criteria
K-1
Uses software
tools for analysis
K-2
Uses software
tools to present
data in useful
format (graphs,
numerical, table,
charts, diagrams)
K-3
Uses software
tools to simulate
physical systems
4
Exemplary
3
Proficient
2
Developing
Can use various
software tools
and their
advanced
features correctly
for analysis
Can use various
software tools
and their
advanced
features correctly
for data
presentation
Can use software
tools correctly for
analysis
Can use software
tools for analysis
with only a few
mistakes
Can use software
tools correctly for
data presentation
Can use software
tools for data
presentation with
only a few
mistakes
Can use software
tools and their
advanced
features correctly
for simulation
Can use software
tools correctly for
simulation
Can use software
tools for
simulation with
only a few
mistakes
1
Beginning or
incomplete
Cannot use
software tools for
analysis or
attempts to use
them but with
many mistakes
Cannot use
software tools for
data presentation
or attempts to
use them but with
many mistakes
(missing labels,
etc.)
Cannot use
software tools for
simulation or
attempts to use
them but with
many mistakes
Table 10: OUTCOME K: An ability to use the techniques, skills, and modern engineering tools necessary for engineering practice
QNET ROTPENT Laboratory Manual - Instructor Manual
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References
[1] Quanser Inc. Qnet assessment workbook microsoft excel file, 2011.
[2] Quanser Inc. QNET Rotary Pendulum Control Trainer User Manual, 2011.
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